The present invention relates to methods for controlling the growth of bacteria, fungi and algae. The methods of the invention may be used, for example, for controlling bacteria, fungi and algae which propagate on industrial raw materials and products and in water in circulating water systems.
The bacteria and fungi on industrial raw materials and products degrade the quality of industrial raw materials and products and cause various other troubles. The damage is very serious. The algae which propagate on the bottom of ships cause the slowdown of speed of ships. Bacteria, fungi and algae in water in circulating water systems produce mats of slime which restrict the flow of water and reduce the efficiency of heat exchange. The troubles caused by bacteria, fungi and algae constitute a considerable problem.
Many compounds having bactericidal, fungicidal and algicidal activity have been used for prevention of the damage caused by the bacteria, fungi or algae to industrial raw materials and products and the impediment caused by slime in circulating water systems. These compounds include, for example, organic mercury compounds, organic tin compounds, phenols having substituted halogen atoms, organic sulfur compounds, formalin, cresol and quaternary ammonium salts. These compounds, however, have various defects, for example, strong toxicity against humans and live-stock, pollution of environment, irritative or offensive odor, bad influence upon industrial raw materials and products and weak bactericidal and fungicidal activity.
The compounds of the invention also have remarkable exterminating activity against various kinds of bacteria or fungi which harm agricultural and horticultural plants or crops, and such compounds can be used for a foliar treatment, seed treatment and soil treatment. The compounds of the invention are particularly useful for the prevention of soil-borne plant diseases which are caused by fungi and bacteria living in soil.
An excellent agricultural chemical for the prevention of soil-borne plant disease has not been discovered since the use of organic mercury compounds as agricultural chemicals was prohibited on account of the toxic character of the compounds against men and beasts.